package LeetCode;

import java.util.Scanner;

public class LC_013_RomanToInteger {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        while (sc.hasNext()) {
            String s = sc.nextLine();
            System.out.println(romanToInt(s));
        }
        sc.close();
    }

    private static int romanToInt(String s) {
        int ret = toNumber(s.charAt(0));
        for (int i = 1; i < s.length(); i++) {
            if (toNumber(s.charAt(i - 1)) < toNumber(s.charAt(i)))
                ret += toNumber(s.charAt(i)) - 2 * toNumber(s.charAt(i - 1));
            else
                ret += toNumber(s.charAt(i));
        }
        return ret;
    }

    private static int toNumber(char ch) {
        switch (ch) {
            case 'I':
                return 1;
            case 'V':
                return 5;
            case 'X':
                return 10;
            case 'L':
                return 50;
            case 'C':
                return 100;
            case 'D':
                return 500;
            case 'M':
                return 1000;
        }
        return 0;
    }
}



